自20世纪80年代初以来，该市一直在研究间接饮用水再利用的概念，通过向有限的当地地表水资源补充先进的经处理再生水。这些研究使当地水行业领导人和监管机构相信，这种再利用方法在技术上是可行和安全的。为了最大限度地利用该市北城工厂生产的再生水，圣地亚哥县水务局（SDCWA）和该市合作，为北城的一个间接饮用水再利用项目准备可行性研究。 通过一项公共推广活动，这个术语“再利用”是为这个间接饮用水再利用项目创造的。通过比较城市为北城再生水分配系统（RWDS）编制的成本估算，以及SDCWA/城市为北城再气化项目编制的成本估算，制定了相关项目规模和综合运营方案，目标是最大限度地利用北城工厂的再生水，同时优化项目的混合单位成本。

Since the early 1980s, the City has been studying the concept of indirect potable reuse through supplementing limited local surface water resources with advanced treated reclaimed water. These studies have led local water industry leaders and regulators to believe that this method of reuse is technically feasible and safe. In order to maximize the beneficial reuse of reclaimed water produced at the City's North City plant, the San Diego County Water Authority (SDCWA) and the City teamed up to prepare a Feasibility Study for an indirect potable reuse project at North City. Through a public outreach effort, the term Repurification was coined for this indirect potable reuse project. By comparing cost estimates prepared by the City for the North City Reclaimed Water Distribution System (RWDS), and by the SDCWA/City for the North City Repurification project, relative project sizes and integrated operational scenarios were developed, with the goal of maximizing the beneficial reuse of reclaimed water from the North City plant while optimizing the melded unit cost of the project.